Sad news from OSH from all the way back on Thursday, when a Lake Renegade crashed during departure from the seaplane base.One 71 year old lady had died from injuries on Friday, bringing this hammer event to a sad ending.

Note: The only picture we received from the whole week of seaplaning activity during Airventure 2017, so whoever was in OSH and failed to send pictures or at least a small write-up on their visit to Seaplanemagazine.com --- Big SHAME! We definitely have some ignorant folks out there....

On the accident sites where people get to speculate, the trim-tab is mentioned. Does it look normal?I have no clue, not a real pilot and no clue about Lake's. Is this up from the impact or something?

That is sad news, especially with the loss of life. It is bad for the seaplane industry / community - and it is also sad that there was not much else in the way of news to come out of Oshkosh too, at least in terms of seaplane news in particular. Except for the few press releases from Wipaire and Aerocet that were reported on Seaplanemagazine.com...

My question with regard to that trim tab is... (Maybe John S. aka SkimmerOne knows...) Is it a standard trim tab, or is it an anti-servo tab?

If the former, that looks "bad" to me and seems like it would cause the seaplane to dive down or dig into the water; if the latter, maybe not so much. Need to know more about the LA-4-250 Renegade's particular system...

Some bystanders reported that it hit a rogue wave - but in the photos posted on the Kathryn's report site, I did not see anything like that over the course of several "action" shots of the actual accident.

Aircraft went down in heavy water as is common when wind is out of the North-North East on Winnebago. I will not speculate as lives were lost but it was very rough water when he departed.

I landed on Thursday in 10 knot winds with 2 foot swells and almost knocked out my molars in my 180. There was a Lake that landed miles south and was trying to taxi in that morning and called a mayday as he was taking on water under taxi. I assume he made it in as I never heard anything else other than the radio call.

When they removed operations from the "cut" for take off and landing they forced all of us to head into rough water as there is no flat water save the little area by Warbird Island when the wind is out of the north. I fear the repercussion of this may be a ban on operations at times due to water conditions (base closed to traffic). The Blues are a great draw but their TFR pretty much kills all flying in the afternoon hours anyways.

Yes, you are correct. Mention has been made of the trim tab. Yes, it was in the full nose - up position. The flaps were also in the full up position. The flight manual calls for flaps to be down for all takeoffs and landings. Operating speed limitation is 125mph. Both the 200 HP Buccaneer and the 250/270 HP Renegade take off from land or water at about 60 mph. The flaps are set at 20 degrees and are slotted, low speed-high-lift and are about 14 feet in length and when they are extended down and rearward, practically double the lift of the wing. The nose tends to go down with flap extension, hence the use of up trim.

If flaps are not used either intentionally or the pilot forgets them, the aircraft flies very much differently. The speed at lift off is now raised considerably and should the pilot try to rotate the attitude for what he believes to be a normal flaps-down takeoff, the result is now a very nose high attitude exacerbated by full up trim and wave action. It takes a super pilot to realize what is happening at this point.Lake pilots are taught a correct attitude for take off which is just slightly nose high which allows the speed to build to takeoff speed without any obvious "rotation" at lift off, and this should happen around 60mph in a fairly flat attitude. If one pulls the nose up during the takeoff run, the tail goes down and the speed reduces and it also gives the wings an angle of attack, however that slows the aircraft further, resulting in no lift-off.

Lake trimming is different from any other system. Because it is a pusher it requires lots of up trim at full power, but we also have to trim it for a glide also, which has a total lack of thrust. We have to trim it differently for the load it is carrying in the cockpit, all forward of the center of gravity. We have to trim it for water step taxiing and lift-off speeds and in between. The trim differs from model to model, whether it is a 150HP C-1 Skimmer or a 270HP Renegade. My Skimmer #1 has a trim tab on each elevator similar to most aircraft built in the 1940s. I have lots of time in other C-1 Skimmers with 150 horsepower and there was enough trim. However, Skimmer One now has 160HP and the same trim system, which is barely adequate, depending on the load. I now have to have the elevator full up for a step taxi and liftoff, due to the nosedown thrust. Reducing the throttle slightly helps.

So you see, it is a fairly complex arrangement to cover all the attitudes, power settings, loads, drag of the water.After having said all this. The problem is usually the pilot forgetting a checklist and leaving the flaps up for a water takeoff and then trying to fly the machine as tho the flaps were down. An excellent reason for leaving the flaps down when parked on land or water....lest we forget....it is a different airplane without them.

Great explanation. I think it is easy to see why most, if not all, insurance companies require both considerable initial training and recurrency training by a Lake certified instructor to get coverage.

Bob

SUPPORTING MEMBER

BobWest Nyack Aviation, L.L.C. New York, New York - East Hampton, New York & Warwick, New York 631.374.9652rkittine@aol.com WA2YDV

Thanks John. That was a great, very well-written explanation of the trim issue on Lakes - regardless of whether or not it turns out to be a contributing factor in this particular and tragic fatal accident. Maybe Jason could convince you to turn that into a more extensive "pilot report" or training article for publication on seaplanemagazine.com...

Preliminary report published online by NTSB - confirming trim tab and flap issues - plus adding comment about apparent rush to start the engine and that the airplane "went to full power within two seconds."